Underwater tunnel construction method using tunnel modules, and underwater tunnel constructed thereby

ABSTRACT

The present invention relates to: an underwater tunnel construction method for constructing an underwater tunnel by successively coupling new tunnel modules to the end of an already-constructed body part while moving a launching girder forward, wherein the new tunnel modules are sunk up to the opening of the launching girder and then introduced into the launching girder by using guide cables; and an underwater tunnel constructed by the construction method.

TECHNICAL FIELD

The present disclosure relates to a method for constructing an underwater tunnel that allows vehicles or pedestrians to pass and an underwater tunnel constructed by the construction method. The present disclosure corresponds to the research result of the research project (Name: Smart underwater tunnel system research center) of government sponsored research project (Project Serial Number: 2017R1A5A1014883/Administrative Agent: National Research Foundation of Korea) funded by the Ministry of Science and ICT.

BACKGROUND ART

Technology to construct an underwater tunnel that allows vehicles or pedestrians to pass is disclosed by Korean Patent No. 10-0797795. Another underwater tunnel construction method uses a launching girder and a tunnel module. The launching girder is installed at the end of a pre-installed already-constructed body part such that it can move forward. The tunnel module is fabricated as a box type precast concrete member. According to the conventional art, the following processes are performed in a sequential order.

-   -   a task of delivering a new tunnel module into an internal space         of a launching girder;     -   a task of coupling the new tunnel module to the end of the         already-constructed body part in the launching girder;     -   a task of advancing the launching girder to the front side of         the coupled new tunnel module;     -   a task of repeatedly performing the above-described tasks.

In the above-described process, one of the important tasks is the delivery of the new tunnel module into the launching girder. The new tunnel module is transported to the site while it floats on the water s face or is submerged in the water near the water surface. The task of safely submerging the new tunnel module transported to the site in the water and accurately aligning with the location of the opening of the launching girder and the subsequent task of delivering the new tunnel module into the internal space of the launching girder are very important. Additionally, it is very important to perform the task of delivering the new tunnel module into the internal space of the launching girder safely, precisely and efficiently.

DISCLOSURE Technical Problem

The present disclosure is directed to providing technology to construct an underwater tunnel using a new tunnel module. Specifically, the present disclosure is directed to providing technology to deliver a new tunnel module in water and deliver it into a launching girder. In particular, the present disclosure is directed to providing technology to perform a task of delivering a new tunnel module into a launching girder safely, accurately and efficiently with the minimized work by divers.

The present disclosure is further directed to providing technology to perform a task of coupling and installing a new tunnel module at an end of an already-constructed body part within a launching girder, and a task of advancing the launching girder to the front side of the coupled new tunnel module very efficiently.

Technical Solution

The present disclosure provides an underwater tunnel construction method including, while a launching girder having an opening is coupled and installed at a front end of an already-constructed body part, transporting a new tunnel module to a site using a transport device, submerging the new tunnel module in water, delivering the new tunnel module into an internal space of the launching girder through the opening, coupling and installing the new tunnel module at the end of the already-constructed body part, moving the launching girder forward, and repeatedly performing the above-described process to construct an underwater tunnel.

Additionally, the present disclosure provides an underwater tunnel constructed by the underwater tunnel construction method.

Advantageous Effects

According to the present disclosure, the underwater tunnel is constructed by integrally connecting new tunnel modules precisely fabricated as a precast concrete structure at the factory in a sequential order in the internal space of the launching girder.

In particular, the present disclosure stably lifts down the new tunnel module along the guide cable in the water and delivers the new tunnel module into the internal space of the launching girder. Accordingly, despite a lot of various obstacle factors such as tides until the new tunnel module reaches the launching girder, the new tunnel module reaches the opening stably and accurately.

Therefore, according to the present disclosure, it is possible to safely deliver the new tunnel module into the internal space of the launching girder and greatly reduce the work by divers compared to the conventional art, thereby reducing the cost and significantly improving the task efficiency.

Additionally, the present disclosure accurately installs the launching girder according to the direction and location of the path along which the underwater tunnel runs and continuously connects and couples new tunnel modules within the launching girder. Therefore, according to the present disclosure, when the underwater tunnel has the curved path, it is possible to construct the underwater tunnel according to the designed curved path with the minimized construction errors of the underwater tunnel.

Additionally, the present disclosure eliminates the task of removing and re-installing the mooring means of the already-constructed body part or any other additional task, thereby performing the successive construction task of the underwater tunnel in the longitudinal direction more rapidly, conveniently and efficiently.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic perspective view showing a launching girder installed at a front end of an already-constructed body part by a construction method according to an embodiment of the present disclosure.

FIG. 2 is a schematic transverse side view of FIG. 1 when viewed in a transverse direction.

FIG. 3 is a schematic perspective view showing a new tunnel module hanging on a transport device according to the present disclosure.

FIG. 4 is a schematic longitudinal front view of FIG. 3 .

FIG. 5 is a schematic transverse side view of FIG. 3 .

FIG. 6 is a schematic assembled perspective view of a transport device, a floating body and a guide cable.

FIG. 7 is a schematic transverse side view of FIG. 6 .

FIG. 8 is a schematic longitudinal side view of FIG. 6 .

FIG. 9 is a schematic longitudinal side view of FIG. 8 showing the downward movement of a lift fastening member and a new tunnel module.

FIG. 10 is a schematic longitudinal side view of FIG. 9 showing a new tunnel module delivered into an internal space of a launching girder.

FIG. 11 is a schematic longitudinal side view of FIG. 10 .

FIGS. 12 to 15 are each schematic longitudinal side views and cross-sectional views of a launching girder installed according to the present disclosure.

FIGS. 16 and 17 are each schematic semi-cross-sectional perspective views of a launching girder installed according to the present disclosure.

FIG. 18 is a schematic semi-cross-sectional perspective view of FIG. 17 showing that a new tunnel module is delivered into a launching girder,

FIGS. 19 and 20 are each schematic semi-cross-sectional perspective views of FIG. 18 .

FIG. 21 is a schematic transverse side view of FIG. 20 .

FIGS. 22 to 24 are each schematic transverse side views of FIG. 21 , sequentially showing a series of processes subsequent to FIG. 21 .

FIGS. 25 and 26 are each schematic perspective views sequentially showing that a push traction device is coupled to a precast tunnel module according to an embodiment of the present disclosure.

FIG. 27 is a schematic perspective view of a push traction device.

BEST MODE

In the specification, a direction in which an underwater tunnel is extended is referred to as a “longitudinal direction”. A direction in which a new tunnel module is joined in the underwater tunnel is referred to as “front”, and the contrary direction is referred to as “rear”. In the specification, a “transverse direction” is a direction perpendicular to the longitudinal direction.

In the present disclosure, when a launching girder that can move forward is installed at an end of an already-constructed body part of the underwater tunnel, the following tasks A) to D) are performed in a sequential order to construct the underwater tunnel.

-   -   A) a task of delivering a new tunnel module: a task of         submerging a new tunnel module fabricated as a precast concrete         member in the water and delivering the new tunnel module into an         internal space of the launching girder.     -   B) a task of coupling the new tunnel module: a task of pushing         back the new tunnel module delivered into the internal space of         the launching girder to couple the new tunnel module to the end         of the already-constructed body part.     -   C) a task of advancing the launching girder: a task of advancing         the launching girder to the front side of the new tunnel module.     -   D) a task of repeatedly performing the tasks A) to C).

FIG. 1 is a schematic perspective view showing the launching girder 1 installed at the front end of the already-constructed body part 100. FIG. 2 is a schematic transverse side view showing of FIG. 1 when viewed in the transverse direction. The front end of the already-constructed body part 100 is an end of a section at which the construction of the tunnel module is completed. The launching girder 1 is movably installed at the front end of the already-constructed body part 100. The launching girder 1 is a structure having the internal space. The rear end of the launching girder 1 is coupled and installed at the front end of the already-constructed body part 100. The front end of the already-constructed body part 100 is inserted into the internal space of the launching girder 1 through the rear end of the launching girder 1. In this way, the launching girder 1 is installed at the end of the already-constructed body part 100.

A switch coupling device is equipped at the rear end of the launching girder 1. When the front end of the already-constructed body part 100 is installed in the internal space of the launching girder 1, by the ON/OFF operation of the switch coupling device, the launching girder 1 is fixed in an “immovable state” or coupling is disconnected to bring the launching girder 1 into a “movable state” in which the launching girder 1 can move forward. The switch coupling device may come in various forms using the known technology.

As shown in FIG. 1 , the launching girder 1 has an opening 15. The new tunnel module 200 is delivered into the launching girder 1 through the opening 15. As shown in FIG. 2 , a cable bobbin 40 is coupled and installed on each of two transverse sides of the opening 15. A guide cable 4 is wound on the cable bobbin 40. The plurality of cable bobbins 40 is provided. A floating body 41 is coupled to the upper end of the guide cable 4. The floating body 41 may be an elongated member extended in the longitudinal direction. In this case, all the upper ends of the plurality of guide cables 4 arranged on one transverse side of the opening 15 may be coupled to one floating body 41. However, the respective floating body 41 may be coupled and provided at the upper end of each guide cable 4. When the guide cable 4 is unwound from the cable bobbin 40, the floating body 41 moves up and floats on the water surface directly above the opening 15 or in the water near the water surface.

The new tunnel module 200 is pre-fabricated as a precast concrete member. The new tunnel module 200 is fabricated on the ground or watercraft in the shape of a box having a hole that allows vehicles or people to pass. The new tunnel module 200 is submerged in the water while hanging on a transport device 6 including a pontoon. The new tunnel module 200 is delivered into the internal space of the launching girder 1 through the opening 15.

FIG. 3 is a schematic perspective view showing the new tunnel module 200 hanging on the transport device 6 according to the present disclosure. FIG. 4 is a schematic longitudinal front view of FIG. 3 . FIG. 5 is a schematic transverse side view of FIG. 3 .

The transport device 6 includes the pontoon 60 and a lift fastening member 61. The pontoon 60 is a member that floats on the water surface. In the embodiment shown in the drawings, the pontoon 60 is a member extended to a predetermined length in the longitudinal direction. In particular, in the embodiment of the drawings, two pontoons 60 are arranged side by side at an interval in the transverse direction. Additionally, a working deck 62 extended in the transverse direction is positioned on the pontoons 60. The working deck 62 and the two pontoons 60 are combined into one.

The lift fastening member 61 is hanging on the pontoons 60 by a submerged wire 7. The lift fastening member 61 is separably fastened to the new tunnel module 200. The lift fastening member 61 is lifted down by the relaxation of the submerged wire 7.

The working deck 62 includes a motor M. The motor M pulls or releases the submerged wire 7. The submerged wire 7 has one end coupled to the motor M and the other end vertically extended downward from the working deck 62. The other end of the submerged wire 7 is coupled to the lift fastening member 61. When the submerged wire 7 is pulled by the operation of the motor M, the lift fastening member 61 is lifted up. When the submerged wire 7 is extended downward by the operation of the motor M, the lift fastening member 61 is lifted down. In the embodiment shown in the drawings, the working deck 62 has a hole. The submerged wire 7 coupled to the motor M passes through the hole.

The lift fastening member 61 is a member that is fastened to the new tunnel module 200. When submerging the new tunnel module 200, since the lift fastening member 61 and the new tunnel module 200 are coupled to each other, the new tunnel module 200 hangs down from the lift fastening member 61. After the new tunnel module 200 is delivered into the internal space of the launching girder 1, the lift fastening member 61 and the new tunnel module 200 are separated from each other. The coupling and decoupling of the lift fastening member 61 and the new tunnel module 200 may be performed by the operator's remote control.

The lift fastening member 61 is fastened to or separated from the guide cable 4 where necessary. The lift fastening member 61 is lifted up and down while being fastened to the guide cable 4. To this end, the lift fastening member 61 has a cable through-hole 610 through which the guide cable 4 passes. The cable through-hole 610 runs up to the side of the lift fastening member 61 to easily insert and fasten the guide cable 4 to the cable through-hole 610. In this configuration, the guide cable 4 is inserted from the side of the lift fastening member 61, and is disposed in the cable through-hole 610 through the lift fastening member 61. A blocking pin 611 may be provided to prevent the unwanted slip of the guide cable 4 from the cable through-hole 610. The cable through-hole 610 has an opening into which the guide cable 4 is inserted from the side. The blocking pin 611 is installed at the opening of the cable through-hole 610 to close the opening of the cable through-hole 610.

In the embodiment shown in the drawings, the lift fastening member 61 is a member extended in the transverse direction. Additionally, in the embodiment shown in the drawings, a plurality of lift fastening members 61 is installed at an interval in the longitudinal direction. In the embodiment shown in the drawings, the cable through-hole 610 is formed at each of two transverse ends of the lift fastening member 61.

The new tunnel module 200 is hanging on the transport device 6 including the pontoons 60. The new tunnel module 200 is fastened to the lift fastening member 61 and is disposed in the water below the lift fastening member 61. Additionally, the lift fastening member 61 is hanging on the working deck 62 and the pontoons 60 by the submerged wire 7.

FIG. 6 is a schematic perspective view showing that the transport device 6 on which the new tunnel module 200 is hanging arrived at the floating location of the floating body 41 of the guide cable 4. FIG. 7 is a schematic transverse side view of FIG. 6 . FIG. 8 is a schematic longitudinal side view of FIG. 6 .

The guide cable 4 is extended from the two sides of the opening 13 of the launching girder 1. The floating body 41 is coupled to the guide cable 4. Accordingly, the floating body 41 floats directly above the opening 13 or the nearby water surface or in the water near the water surface. The new tunnel module 200 is fastened to and hangs on the fastening member 61 of the transport device 6. The transport device 6 in this state approaches an area directly above the opening 15 or the water surface at the site in the area, and meets the floating body 41. In this instance, the floating body 41 is fixed to the transport device 6 automatically or by the operator's manual task. As shown in the drawings, the floating body 41 may be brought into close contact with the pontoons 60 of the transport device 6 and fixed to the transverse side or the lower surface.

Before, after or during the task of fixing the floating body 41 to the transport device 6, the lift fastening member 61 is fastened to the guide cable 4. That is, the guide cable 4 is inserted into and passes through the cable through-hole 610 of the lift fastening member 61.

Subsequently, the submerged wire 7 is vertically extended downward by the operation of the motor M installed at the transport device 6. Accordingly, the lift fastening member 61 and the new tunnel module 200 coupled to the lift fastening member 61 are lifted down. As the guide cable 4 is inserted into and passes through the cable through-hole 610 of the lift fastening member 61, the lift fastening member 61 is lifted down along the guide cable 4 while being fastened to the guide cable 4. FIG. 9 is a schematic longitudinal side view of FIG. 8 . FIG. 9 shows the downward movement of the lift fastening member 61 and the new tunnel module 200 subsequent to FIG. 8 .

As the lower end of the guide cable 4 is extended to the transverse side of the opening 15 of the launching girder 1, the lift fastening member 61 and the new tunnel module 200 are lifted down along the guide cable 4 in the direction in which the guide cable 4 is extended, and reaches the opening 15 of the launching girder 1. After the new tunnel module 200 reaches the opening 15, the new tunnel module 200 is delivered into the internal space of the launching girder 1 through the opening 15. FIG. 10 is a schematic longitudinal side view of FIG. 9 . FIG. 10 shows the new tunnel module 200 delivered into the internal space of the launching girder 1 subsequent to FIG. 9 .

After the new tunnel module 200 is delivered into the internal space of the launching girder 1, decoupling of the new tunnel module 200 and the lift fastening member 61 is done to separate them. Additionally, the submerged wire 7 is wound and pulled up by the operation of the motor M installed at the transport device 6 to lift up only the lift fastening member 61. In this instance, the guide cable 4 may keep passing through the cable through-hole 610 of the lift fastening member 61. FIG. 11 is a schematic longitudinal side view of FIG. 10 . FIG. 11 shows that the new tunnel module 200 and the lift fastening member 61 are separated from each other and the lift fastening member 61 is lifted up close to the water surface subsequent to FIG. 10 .

As described above, in the present disclosure, when lifting down the new tunnel module 200 by the submerged wire 7 and delivering the new tunnel module 200 into the internal space of the launching girder 1 through the opening 15 of the launching girder 1, the new tunnel module 200 is lifted down along the guide cable 4. That is, while the launching girder 1 and the transport device 6 are connected with the guide cable 4 at the location of the opening 15, the new tunnel module 200 is lifted down along the guide cable 4.

When the submerged wire 7 is relaxed and extended downward, the new tunnel module 200 is lifted down generally vertically. However, the launching girder 1 is located deep in the water and there are a variety of factors that obstruct the vertical downward movement of the new tunnel module 200 in the water such as tides. Accordingly, it is impossible to guarantee the vertical downward movement of the new tunnel module 200 by simply lifting down the new tunnel module 200 by its own weight at the location directly above the opening 15. Additionally, itis impossible to guarantee the safe delivery of the new tunnel module 200 into the opening 15 of the launching girder 1.

However, in the present disclosure, the launching girder 1 is connected to the transport device 6 with the guide cable 4 at the location of the opening 15 of the launching girder 1, the new tunnel module 200 is coupled to the lift fastening member 61, and the lift fastening member 61 is lifted down with the guidance of the guide cable 4. Accordingly, despite a lot of various obstacle factors such as tides until the new tunnel module 200 and the lift fastening member 61 reach the opening 15, the new tunnel module 200 and the lift fastening member 61 reach the opening 15 stably and accurately. Accordingly, the new tunnel module 200 is safely delivered into the internal space of the launching girder 1 through the opening 15. In this process, it is possible to remarkably reduce the work by divers compared to the conventional art.

When simply submerging only the new tunnel module in the water without the guide cable 4, it is necessary to detect the location of the new tunnel module in the water and perform control to submerge the new tunnel module in the accurate direction. However, underwater location measurement and estimation is a very difficult and complicated process, it requires a large amount of labor, cost and time to measure and control the location of the new tunnel module in the water. In the present disclosure, as described above, the new tunnel module 200 reaches the opening 15 safely and accurately with the guidance of the guide cable 4. In this process, there is no need for location measurement or estimation of the new tunnel module in the water, and any special manual control over location and immersion direction. Accordingly, it is possible to reduce labor and cost, thereby achieving cost efficient construction. That is, according to the present disclosure, it is possible to minimize the work by divers when submerging the new tunnel module 200 in the water and delivering the new tunnel module 200 into the launching girder 1 through the opening 15. Additionally, it is possible to minimize the use of costly underwater location measurement equipment and underwater location control equipment. It is possible to perform the task of submerging the new tunnel module in the water and delivering the new tunnel module into the launching girder 1 safely, accurately and efficiently. Accordingly, it is possible to minimize the underwater tunnel construction cost, reduce safety incidents or accidents and minimize construction errors, thereby achieving precise construction.

After the new tunnel module 200 is delivered into the internal space of the launching girder 1, “the task of coupling the new tunnel module” to couple the new tunnel module 200 to the already-constructed body part 100 and the subsequent “task of advancing the launching girder” are performed in a sequential order. In this instance, concurrently with or subsequent to the above-described tasks, the transport device 6 including the lift fastening member 61 that has been lifted up is moved forward to a location where the launching girder 1 will move. Before moving the transport device 6 forward, the floating body 41 may be separated from the transport device 6, and the guide cable 4 may be separated from the lift fastening member 61. In this case, when the task of advancing the launching girder 1 is performed, the floating body 41 and the guide cable 4 also move forward together. The operator can move the transport device 6 carrying the new tunnel module to the accurate construction site using the floating body 41 as a guide.

After the task of advancing the launching girder 1 and the task of moving the transport device 6 forward are performed, another new tunnel module hangs on the transport device and is transported to the construction site. The above-described series of processes including the process of coupling the transport device to the floating body is repeatedly performed to complete the construction of the underwater tunnel.

The task of coupling the new tunnel module to couple the new tunnel module 200 to the already-constructed body part 100 in the internal space of the launching girder 1 and the subsequent task of advancing the launching girder may be performed by the following process. The new tunnel module 200 is delivered into the launching girder 1. Subsequently, the new tunnel module 200 is pushed rearward using the launching girder 1 as a reaction force support point to couple the new tunnel module 200 to the front end of the already-constructed body part 100. Subsequently, the launching girder is moved forward using the coupled new tunnel module as a new reaction force support point. The new tunnel module fabricated as a precast member is delivered into the advanced launching Order again. This process is repeatedly performed to construct the underwater tunnel.

FIGS. 12 to 15 are each schematic longitudinal side views and cross-sectional views of the launching girder 1 when installed. FIG. 12 is a schematic side view of FIG. 1 when viewed from the rear side in the longitudinal direction as indicated by the arrow E. FIG. 13 is a schematic longitudinal cross-sectional view of FIG. 1 , taken along the line F-F, FIG. 14 is a schematic longitudinal cross-sectional view of FIG. 1 , taken along the line G-G. FIG. 15 is a schematic longitudinal cross-sectional view of FIG. 1 , taken along the line H-H.

FIGS. 16 and 17 are each schematic semi-cross-sectional perspective views of the launching girder 1. FIG. 16 is a schematic transverse semi-cross-sectional perspective view of FIG. 12 taken along the line J-J, when the launching girder 1 is not coupled to the front end of the already-constructed body part 100. FIG. 17 is a schematic transverse semi-cross-sectional perspective view of FIG. 12 taken along the line J-J, when the launching girder 1 is coupled to the front end of the already-constructed body part 100. FIG. 18 is a schematic semi-cross-sectional perspective view of FIG. 17 . FIG. 18 shows that the new tunnel module 200 fabricated as a precast concrete member and transported is delivered into the launching girder 1.

The launching girder 1 is installed at the end of the already-constructed body part 100 to insert the front end of the already-constructed body part 100 into the internal space of the launching girder 1. The launching girder 1 is coupled to the end of the already-constructed body part 100. In this instance, the launching girder 1 may be switched from/to an “immovable state” to/from a “movable state” by the operation of the switch coupling device. The switch coupling device enables strong coupling between the rear end of the launching girder 1 and the front end of the already-constructed body part 100 or loosens the coupling to bring the launching girder 1 into the movable state. In FIG. 12 , the reference numeral 210 denotes the switch coupling device. The switch coupling device 210 may be fabricated by the known technology and its detailed description is omitted.

A push traction device 3 is installed in the launching girder 1. If necessary, a movement guide 2 may be installed to easily move the delivered new tunnel module 200 rearward. The movement guide 2 is a member that guides the rearward movement of the delivered new tunnel module 200. In the embodiment shown in the drawings, the movement guide 2 is formed in the shape of a base plate having rolling wheels on bottom. In the embodiment shown in the drawings, the movement guide 2 is placed on the bottom surface of the launching girder 1. Accordingly, in this case, the new tunnel module 200 is placed on the movement guide 2. However, the movement guide 2 is not limited to the shape of the base plate having the rolling wheels. The movement guide 2 may be formed in the shape of a rail that is installed on the bottom surface of the launching girder 1 to allow the new tunnel module 200 to easily slide when placed thereon. The movement guide 2 may be formed in a variety of other shapes for easily moving the new tunnel module 200 rearward. The movement guide 2 is positioned in the launching girder 1.

The push traction device 3 is a device used to push the new tunnel module 200 rearward to join the new tunnel module 200 to the already-constructed body part 100. The new tunnel module 200 delivered into the internal space of the launching girder 1 is aligned in front of the already-constructed body part 100. Subsequently, the push traction device 3 pushes the new tunnel module 200 rearward to join the new tunnel module 200 to the already-constructed body part 100. The push traction device 3 also performs a function to advance the launching girder 1. After the new tunnel module 200 and the already-constructed body part 100 are combined into one, the push traction device 3 advances the launching girder 1. The push traction device 3 includes a rack member 31, a pinion member 32 and a fastening arm 33. The rack member 31 is fixed and installed at the launching girder 1 and is extended to a predetermined length in the longitudinal direction. The pinion member 32 is engaged with the rack member 31 in a “rack and pinion” structure and moves forward and backward in the longitudinal direction. The fastening arm 33 is extended rearward. The fastening arm 33 is separably fastened to the delivered new tunnel module 200. The push traction device 3 will be described in detail below with reference to the drawings.

FIGS. 19 and 20 are each schematic semi-cross-sectional perspective views of FIG. 18 . Each of FIGS. 19 and 20 sequentially shows a process of delivering the new tunnel module 200 into the launching girder 1 and pushing the new tunnel module 200 rearward to couple the new tunnel module 200 to the already-constructed body part 100 in the present disclosure. FIG. 21 is a schematic transverse side view of FIG. 20 . For convenience, FIG. 21 shows an enlarged view of an area at Which the launching girder 1 is installed. In FIG. 21 , the already-constructed body part 100 and the new tunnel module 200 are shown in exterior view, not in cross section, whereas the launching girder 1 is shown in cross section to display the internal space.

When the launching girder 1 is coupled and installed at the front end of the already-constructed body part 100, the new tunnel module 200 is delivered into the launching girder 1 through the opening 15. Additionally, as shown in FIG. 19 , the new tunnel module 200 is positioned in alignment in front of the already-constructed body part 100. In case that the movement guide 2 is provided to assist the movement of the new tunnel module 200, the new tunnel module 200 is placed on the movement guide 2.

The fastening arm 33 is separably fastened to the new tunnel module 200, To this end, an arm fastening jig 34 may be provided at the front end of the new tunnel module 200. The arm fastening jig 34 is pre-installed before delivering the new tunnel module 200 into the water. To deliver the new tunnel module 200 into the launching girder 1, a lifting wire may be connected to the new tunnel module 200 and wound and pulled up in the launching girder 1. The present disclosure is not limited to the above-described method.

Subsequently, as shown in FIG. 20 , the pinion member 32 coupled to the rack member 31 is moved back toward the front end of the new tunnel module 200. Additionally, the fastening arm 33 is fastened to the arm fastening jig 34. The fastening arm 33 and the pinion member 32 move in the longitudinal direction together as one. In the embodiment shown in the drawing, the pinion member 32 is provided in the shape of a wheel of a vehicle. In the embodiment shown in the drawings, the fastening arm 33 is formed in the shape of a rotating arm that can rotate. The fastening arm 33 is coupled to the vehicle. The arm fastening jig 34 may be fabricated as a ring-shaped member. The arm fastening jig 34 may be fixed and installed at the front end of the new tunnel module 200. The end of the fastening arm 33 may be engaged with the ring shape of the arm fastening jig 34. Through this configuration, it is possible to easily couple and decouple the fastening arm 33 and the arm fastening jig 34.

FIGS. 22 to 24 are each schematic transverse side views of FIG. 21 , FIGS. 22 to 24 sequentially show a series of processes subsequent to FIG. 21 . After the fastening arm 33 and the arm fastening jig 34 are fastened, the new tunnel module 200 is pushed and moved toward the end of the already-constructed body part 100 to join the new tunnel module 200 to the already-constructed body part 100. As shown in FIG. 22 , when the pinion member 32 is driven to rotate in a first direction indicated by the arrow B with the fastening arm 33 fastened to the arm fastening jig 34, the pinion member 32 moves rearward on the rack member 31. In FIG. 22 , the dotted line indicates the pinion member 32 before the movement. When the pinion member 32 moves rearward, the launching girder 1 is already firmly coupled to the front end of the already-constructed body part 100 not to move, and the rack member 31 is integrally fixed to the launching girder 1. Accordingly, when the pinion member 32 is driven to rotate in the first direction with the fastening arm 33 fastened to the arm fastening jig 34, the launching girder 1 itself acts as a reaction force support point. Accordingly, the pinion member 32 pushes the new tunnel module 200 toward the front end of the already-constructed body part 100 while moving rearward along the rack member 31. When the new tunnel module 200 is placed on the movement guide 2, the new tunnel module 200 may be pushed rearward very easily.

When the new tunnel module 200 is pushed rearward by the rearward movement of the pinion member 32, the rear end of the new tunnel module 200 and the front end of the already-constructed body part 100 are brought into contact with each other at the accurate location. Subsequently, the new tunnel module 200 is air-tightly connected and joined to the already-constructed body part 100. Accordingly, the already-constructed body part 100 and the new tunnel module 200 are combined into one.

After the already-constructed body part 100 and the new tunnel module 200 are combined into one, decoupling of the launching girder 1 and the already-constructed body part 100 is done to bring the launching girder 1 into the movable state. Additionally, the task of advancing the launching girder 1 is performed to move the launching girder 1 forward. Specifically, when the fastening arm 33 is still fastened to the arm fastening jig 34 of the new tunnel module 200 after the launching girder 1 is brought into the moveable state, the pinion member 32 is driven to rotate in the first direction again. That is, in the same way as pushing the new tunnel module 200 rearward, the pinion member 32 is continuously driven to rotate in the first direction indicated by the arrow B in FIG.

The already-constructed body part 100 and the new tunnel module 200 are combined into one, and the fastening arm 33 is still fastened to the arm fastening jig 34 of the new tunnel module 200. Accordingly, the pinion member 32 cannot move rearward any longer even if the pinion member 32 rotates in the first direction. In contrast, a reaction force generated by the rotation of the pinion member 32 in the first direction is transmitted to the new tunnel module 200 and the already-constructed body part 100 through the fastening arm 33. That is, the already-constructed body part 100 and the new tunnel module 200 combined into one become a new reaction force support point for the reaction force generated by the forward movement of the launching girder 1. Accordingly, when the pinion member 32 in the immovable state in which the pinion member 32 cannot move rearward is continuously driven to rotate in the first direction, a reaction force is generated, and the rack member 31 coupled to the pinion member 32 is moved forward. Accordingly, the launching girder 1 in which the rack member 31 is fixed also moves forward as shown in FIG. 23 . In FIG. 23 , the dotted line indicates the launching girder 1 before the movement.

After the launching girder 1 is moved forward to a necessary distance by the pinion member 32 continuously driven to rotate in the first direction, decoupling of the fastening arm 33 and the arm fastening jig 34 is done to separate them. Additionally, the pinion member 32 is driven to rotate in a second direction (indicated by the arrow D in the drawing) opposite the first direction to move the pinion member 32 and the fastening arm 33 forward as shown in FIG. 24 . That is, the pinion member 32 and the fastening arm 33 are moved to a location for accommodation of a new tunnel module fabricated as a precast member.

When these tasks are completed, the above-described tasks are repeated to construct the underwater tunnel. That is, the following tasks are repeatedly performed in a sequential order.

-   -   A new tunnel module including an arm fastening jig is         transported to the site using the transport device.     -   The new tunnel module is safely lifted down to the accurate         location using the guide cable and is delivered through the         opening of the launching girder.     -   The fastening arm is fastened to the arm fastening jig, and the         new tunnel module is pushed rearward by the rotation of the         pinion member in the first direction and is integrally coupled         in an air-tight manner.     -   The launching girder is brought into the movable state, and is         moved forward by the rotation of the pinion member.     -   The fastening arm and the pinion member are returned to the         original location (a location for accommodation of another new         tunnel module).

FIGS. 25 and 26 are each schematic perspective views sequentially showing that the push traction device 3 is coupled to the new tunnel module 200 according to an embodiment of the present disclosure. FIG. 27 is a schematic perspective view of the push traction device 3. The push traction device 3 includes the rack member 31, the pinion member 32 and the fastening arm 33, in the embodiment shown in the drawings, the rack member 31 has a toothed gear on the upper surface, and two rack members 31 extended in the longitudinal direction are arranged side by side. The pinion member 32 is formed in the shape of a wheel having a toothed gear. The rack member 31 is engaged with the pinion member 32 in a “rack and pinion” structure. In particular, in the embodiment shown in the drawings, the pinion member 32 is mounted on the vehicle in the shape of a wheel. In the embodiment shown in the drawings, the fastening arm 33 is formed in the shape of a “rotating arm” that is separably fastened to the arm fastening jig 34 by rotation. In the drawings, the reference numeral 320 is a female rotating shaft 320 provided in the vehicle for the rotation of the fastening arm 33. The reference numeral 340 is a rotation driving device 340 for rotating the fastening arm 33. In this configuration, as described with reference to FIGS. 19 and 20 , when the new tunnel module 200 is delivered into the launching girder 1 through the opening 15 of the launching girder 1, the pinion member 32 is moved toward the front end of the new tunnel module 200. Additionally, the fastening arm 33 is fastened to the arm fastening jig 34 by rotation. The foregoing description is an example embodiment of the push traction device 3 of the present disclosure, and the present disclosure is not limited to the above-described embodiment.

The launching girder 1 is installed at the end of the already-constructed body part 100, the new tunnel module fabricated as a precast member is delivered into the launching girder 1 and coupled to the already-constructed body part 100, and the delivery and connection of the new tunnel module is repeatedly performed with the sequential forward movement of the launching girder 1, to construct the underwater tunnel. The present disclosure can be applied and used very effectively even when the path along which the underwater tunnel runs is a curve shape. In particular, the present disclosure accurately installs the launching girder 1 according to the direction and location of the path along which the underwater tunnel runs. Accordingly, it is possible to minimize construction errors and connect and couple new tunnel modules fabricated at the factory rapidly within the launching girder 1. Accordingly, it is possible to significantly improve the tunnel construction efficiency, thereby reducing the total construction period and cost of the underwater tunnel.

Additionally, the conventional art involving extruding new tunnel modules in a sequential order needs to install a loading apparatus and retaining walls to extrude the new tunnel modules. Additionally, in the conventional art, extrusion is performed with the increased load capacity. As opposed to the conventional art, the present disclosure connects new tunnel modules fabricated at the factory within the launching girder 1. Accordingly, according to the present disclosure, it is possible to omit to install the loading apparatus and the retaining walls or at least reduce the scale, thereby reducing the cost incurred for the installation and maintenance of the equipment.

INDUSTRIAL APPLICABILITY

The present disclosure can be used to construct underwater tunnels very usefully. 

1. An underwater tunnel construction method; comprising: While a launching girder (1) having an opening (15) is coupled and installed at a front end of an already-constructed body part (100), transporting a new tunnel module (200) to a site using a transport device (6), submerging the new tunnel module (200) in water, delivering the new tunnel module (200) into an internal space of the launching girder (1) through the opening (15), coupling and installing the delivered new tunnel module (200) at the end of the already-constructed body part (100), moving the launching girder (1) forward, and repeatedly performing this process to construct an underwater tunnel, wherein the transport device (6) includes a pontoon (60) which floats, and a lift fastening member (61) which is separably fastened to the new tunnel module (200), wherein the lift fastening member (61) has a cable through-hole (610), and is lifted up and down by relaxation of a submerged wire (7) while hanging on the pontoon (60) by the submerged wire (7), and a floating body (41) is coupled to an upper end of a guide cable (4) fixed to two transverse sides of the opening (15) of the launching girder (1), and floats in water; and the underwater tunnel construction method comprises: moving the transport device (6) to the site with the new tunnel mod e (200) fastened to the lift fastening member (61), fixing the floating body (41) to the transport device (6), and allowing the guide cable (4) to pass through the cable through-hole (610) of the lift fastening member (61); lifting down the new tunnel module (200) along the guide cable (4) by the relaxation of the submerged wire (7) with the lift fastening member (61) fastened to the guide cable (4) to allow the new tunnel module (200) to reach the opening (15) of the launching girder (1), and delivering the new tunnel module (200) into the internal space of the launching girder (1) through the opening (15); integrally joining the new tunnel module (200) to the already-constructed body part (100) in the launching girder (1); and advancing the launching girder (1).
 2. The underwater tunnel construction method according to claim 1, wherein the transport device (6) includes two pontoons (60) arranged side by side at an interval in the transverse direction, each pontoon (60) being a member extended to a predetermined length in a longitudinal direction; a working deck (62) extended in the transverse direction is positioned on the two pontoons (60) and is coupled to the pontoons (60), and the two pontoons (60) and the working deck (62) are combined into one, the working deck (62) includes a motor (M) and has a hole, and the submerged wire (7) is vertically extended downward from the working deck (62) through the hole with one end coupled to the motor (M), and is coupled to the lift fastening member (61).
 3. The underwater tunnel construction method according to claim 1, wherein a push traction device (3) is provided in the launching girder (1), and includes a rack member (31) which is extended in a longitudinal direction and is fixed and installed in the launching girder (1), a pinion member (32) which is engaged with the rack member (31) in a rack and pinion structure and moves forward and rearward in the longitudinal direction, and a fastening arm (33) which is extended rearward, the step of integrally joining the new tunnel module (200) to the already-constructed body part (100) in the launching girder (1) comprises performing a process of after delivering the new tunnel module (200) fabricated as a precast concrete member into the launching girder (I), driving the pinion member (32) to rotate in a first direction to move toward a front end of the new tunnel module (200), and fastening the fastening arm (33) to the new tunnel module (200), and performing a process of while the launching girder (1) is brought into an immovable state, driving the pinion member (32) to rotate in the first direction to move rearward to push the new tunnel module (200) toward the already-constructed body part (100) and integrally join the new tunnel module (200) to the already-constructed body part (100), and the step of advancing the launching girder (I) comprises performing a process of bringing the launching girder (1) into a movable state, and continuously driving the pinion member (32) to rotate in the first direction to advance the launching girder (1), and performing a process of separating the fastening arm (33) from the new tunnel module (200), and driving the pinion member (32) to rotate in a second direction to move the pinion member (32) forward.
 4. The underwater tunnel construction method according to claim 3, wherein the rack member (31) is extended in the longitudinal direction and is fixed and provided in the launching girder (1), the pinion member (32) is provided in a shape of a wheel of a vehicle and is engaged with the rack member (31) in the rack and pinion structure, the fastening arm (33) is rotatably installed at the vehicle including the pinion member (32), and an arm fastening jig (34) is provided at the front end of the new tunnel module (200), and the fastening arm (33) is separably fastened to the arm fastening jig (34) by rotation.
 5. An underwater tunnel constructed by sequentially connecting tunnel modules in a forward direction in water, each tunnel module having a hole through which vehicles or people pass, wherein the underwater tunnel is constructed by the underwater tunnel construction method of claim and has a successive connection structure of the tunnel modules. 